Sub gifts get a digital card customised and based upon the streamer, much like dangheeseling does for his community where a gift sub opens a random card pack, also available in channel points, this would be a great idea if across the whole of twitch you could earn card packs based upon the individual streamers for gifting in those channels or use channel points to obtain a pack, and complete your collection or even trade with others for cards, a great way to encourage gifted subs and engage communities with collectable trading cards from gifted subs.